SLD (Second-Level Domain)
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The SLD (second-level domain) is the part of a domain name directly to the left of the [[tld|TLD]]. It is typically the unique, brandable portion that a [[registrant]] chooses during [[domain-registration|registration]].
Example
In 'example.com', 'example' is the SLD. Some ccTLDs have functional SLDs like 'co' in example.co.uk.
Referenced in Guides
Domain Basics